1. Field of the Invention
The present invention relates to the field of circuit testers and particularly to systems for testing digital integrated circuits.
2. Discussion of Related Art
Modern integrated circuits are very complex in nature. The testing of the electrical characteristics of these circuits is of critical importance in order to ensure reliability. However, because of the complex nature of integrated circuits and because of the constant improvement of circuits and development of new circuits, testing to ensure good quality control can be a very difficult and complex problem.
Various circuit testers have been suggested. For example, U.S. Pat. No. 4,517,661 to Graf et al shows a programmable chip tester having plural pin unit buffers which each store sufficient test data for independent operations by each pin unit.
U.S. Pat. No. 4,066,882 to Esposito shows a digital stimulus generating and response measuring system.
U.S. Pat. No. 4,125,763 to Drabing et al shows an automatic tester for microprocessor boards.
U.S. Pat. No. 4,168,527 to Winkler shows an analog and digital circuit tester.
U.S. Pat. No. 4,168,796 to Fulks et al shows a portable tester for testing a variety of printed circuit boards without utilizing specialized adaptor boards for rerouting input test signals and supply voltages from the tester to various pins of the board under test.
U.S. Pat. No. 4,194,113 to Fulks et al shows a method and apparatus for isolating faults in digital printed circuit boards under test.
U.S. Pat. No. 4,308,615 to Koegel et al discloses an apparatus for use in automatic testing of elements in data processing systems.